JP2002096107A - Rolling mill - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a rolling mill capable of improving its rolling efficiency because of alleviating its vibration which occurs during rolling by increasing the horizontal rigidity of the rolling mill to work rolls and a backup roll. SOLUTION: A housing 1 for the rolling mill holds one pair of upper and lower work rolls 2, and a roll chock 3 which pivots the work rolls 2. At least on one side of the housing 1, a hydraulic cylinder 6 is placed, the tip of its piston 5 is provided with a liner 4 which is brought into contact with a roll chock 3. The piston 5 of the hydraulic cylinder 6 is brought into contact, at a retracted position, with a shaft 9' which is introduced into the hydraulic cylinder 6 by means of a screw 9 and is fixed there. This increases the horizontal rigidity of the rolling mill.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rolling mill, and more particularly, to a rolling mill configured to prevent vibrations generated in the traveling direction of a strip or a steel bar when rolling the strip or the bar.

[0002]

2. Description of the Related Art As conventional rolling mills, general four-high rolling mills and four-high cross rolling mills will be described. In the rolling mill shown in FIG. 13, a work roll 2 and a backup roll 22 are mounted on a roll chock 3 and a roll chock 25, respectively. In the case of not the cross rolling mill shown in FIG. 13A, a housing liner 23a is arranged between the inside of the housing 1 and the roll chocks 3 and 25, while in the case of the cross rolling mill shown in FIG. A pair of crossheads 23b for crossing the work roll 2 and the backup roll 22 are disposed between the inside of the housing 1 and the roll chocks 3 and 25, and these components are installed above and below the pass line of the housing 1. Have been.

[0003] Reference numeral 24 denotes a pressure reducing means.
The lower end thereof is attached to the roll chock 25, and is vertically expanded and contracted by a rolling-down device (not shown). The roll gap between the upper and lower work rolls 2 is set to an appropriate value via the roll chock 25 and the backup roll 22. Then, the conveyed strip 21 is bitten between the work roll gaps, and receives a rolling load from the pressing means 24 while rotating the upper and lower work rolls 2 and the backup roll 22, so that the strip 21 has a predetermined thickness. Rolled into thin steel. At the time of rolling, a large rolling load is applied to the housing 1, and as shown in FIG. 14, a reaction force F of the rolling load acts on the upper portion of the housing 1, the side of the housing 1 is narrowed, and the deformation δo is formed. Happens.

In the case of the cross rolling mill shown in FIG. 13 (b), the cross head 23b is displaced by a cross screw or a hydraulic cylinder 26 which is in mechanical contact with the cross roll 23b, and the work roll 2 and the backup Roll 2
Position the cross point of No. 2. At this time, in the rolling state in which the rolling load F is applied, the hysteresis of the vertical control of the housing 1 with respect to the work roll 2 is minimized, and the rolled plate thickness is controlled with high accuracy. Roll chock 3 and 25 for the purpose of easy roll change
A gap δ ′ shown in FIG. 15 is provided between the head and the crosshead 23b by a pullback cylinder 27.

[0005] Even when the rolling mill is not the cross rolling mill shown in Fig. 13 (a), for the same reason as in the case of the cross rolling mill, the deformation of the inner narrowing amount δo on the side portion of the housing 1 in the rolling state in which the rolling load F is applied is reduced. In the raised state, a gap δ 'is provided between the housing liner 23a and the roll chocks 3 and 25.

As described above, in the conventional rolling mill, the housing 1 is narrowed inward by the rolling load at the time of rolling.
Even if there is a deformation, there is a gap of about 0.2 mm to 1 mm, for example, as a gap δ ′ between the roll chocks 3 and 25 and the housing liner 23a and the crosshead 23b. In some cases, the horizontal dynamic rigidity was low. For this reason, when rolling is performed at a high-pressure reduction and a high-pressure reduction in a state where the horizontal dynamic rigidity is low, a large vibration which is considered to be caused by the friction between the rolled material and the rolling roll occurs in the rolling roll, the housing, etc., This hindered high-efficiency rolling.

[0007]

SUMMARY OF THE INVENTION The present invention increases the horizontal rigidity of a rolling mill with respect to a work roll or a work roll and a backup roll, and reduces the vibration of the rolling mill during rolling without hindering the control of the thickness. An object of the present invention is to provide a rolling mill capable of reducing the rolling efficiency and improving the rolling efficiency.

[0008]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention provides a pair of upper and lower work rolls, a roll chock that supports the work rolls, and a roll chock that is horizontally mounted in a housing of a rolling mill. A rolling mill provided with a hydraulic cylinder on both sides or one side of a housing for pressing, a liner for always pressing the roll chock at a tip of a piston of the hydraulic cylinder in a horizontal direction toward a direction perpendicular to the roll chock; Alternatively, a rolling mill having a configuration having a work roll crosshead is provided.

The rolling mill according to the present invention may be a rolling mill that is not a cross rolling mill, or may be a work roll or a cross rolling mill in which a work roll and a backup roll can be set to a cross angle.

In the rolling mill of the present invention having the above structure, the liner or the work roll crosshead is pressed against the roll chock of the work roll by the hydraulic cylinders provided on both sides or one side of the housing, and the liner and the roll chock or the work roll crosshead are connected to each other. By reducing the gap between the roll chocks to zero and applying an offset force (preload) greater than zero to the hydraulic cylinder to slightly deform the housing, the horizontal dynamic rigidity of the rolling mill with respect to the work roll is improved. By making it large, vibration of the rolling mill during rolling can be reduced, and high-efficiency rolling can be performed.

In the rolling mill according to the present invention, if a rolling element or a grease pad is attached to a contact surface of a liner or a work roll crosshead that comes into contact with the roll chock, the liner and the work roll crosshead that are pressed against the roll chock are provided. Since the vertical friction can be reduced, the vibration of the rolling mill during rolling can be reduced without hindering the thickness control.

Further, in the rolling mill according to the present invention, a shaft for mechanically fixing the retracted position of the piston of the hydraulic cylinder, a screw installed in the housing for displacing the shaft, and a motor for rotating the screw are provided. When the configuration having is adopted, the piston of the hydraulic cylinder that presses the liner or the work roll crosshead against the roll chock is in contact with the back surface of the piston as described above without passing through the rigid oil in the hydraulic cylinder. Since it is fixed to the housing via the shaft and the screw behind the shaft, the horizontal rigidity of the rolling mill can be reliably increased, and horizontal vibration of the rolling mill is less likely to occur.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A rolling mill according to the present invention will be specifically described below with reference to the embodiments shown in FIGS. In the following embodiments, the same components as those of the conventional apparatus shown in FIGS. 13 to 15 are denoted by the same reference numerals for simplification of description, and redundant description thereof will be omitted.

(First Embodiment) First, a rolling mill according to a first embodiment will be described with reference to FIGS. In FIG. 1, reference numeral 6 denotes a hydraulic cylinder, which is disposed on the inner surface side of the cross rolling mill housing 1 facing the roll chocks 3. A liner 4 that is in contact with the roll chock 3 is attached to a tip of the piston 5 of the hydraulic cylinder 6.
At the tip of the liner 4, a rotatable spherical rolling element 16 as shown in FIGS. 2 (a) and 2 (b) or a cylindrical shape having a horizontal axis of rotation as shown in FIG. The rolling element 16 '
It is mounted with its outer peripheral surface slightly projecting from the surface of the liner 4.

The rolling elements 16 (or 16 ') mounted on the liner 4 are appropriately selected in shape, number, mounting location, etc., according to the structure of the rolling mill, the offset force applied to the liner 4 and the required static rigidity. Things. A grease pad 17 as shown in FIGS. 2D and 2E may be used at the tip of the liner 4 instead of the above-mentioned rolling element. In this case, the grease is press-fitted from the side opposite to the surface in contact with the roll chock 3, and the grease is applied to the liner 4 from the cone-shaped portion C.
And spreads thinly on the contact surface between the roller and the chocks 3, so that the resistance to the vertical fluctuation can be reduced without weakening the rigidity.

Rolling elements 16, 16 ', grease pad 17
In addition, as shown in FIG. 2 (f), by installing the laminated rubber 17 'on the liner 4, it is possible to easily move up and down and in the thrust direction easily, and to secure rigidity in the horizontal direction. The laminated rubber 17 ′ is obtained by laminating an oil-resistant rubber 17 ″ and a metal plate 17 ″. The size of the laminated rubber, the rubber thickness, the metal thickness, etc. is determined according to the rigidity required by the device. I do. The piston 5 is connected to a hydraulic cylinder 6 by a hydraulic pipe 7,
It is operated by the hydraulic pressures P1 and P2 supplied from 8 to control the position of the roll chock 3. 6 ″ is a seal.
δ ′ is a gap between the liner 4 and the roll chock 3.

Reference numeral 9 denotes a screw, which is provided behind the hydraulic cylinder 6 with a hole formed in the housing 1. The hole of the housing 1 has a screw structure corresponding to the screw of the screw 9. At the rear end of the hydraulic cylinder 6, a shaft 9 'is introduced through a seal 6'', and the rear end of the shaft 9' is connected to the front end of the screw 9 via a joint 10 '. When the screw 9 is rotated and moved forward, the shaft 9 'is introduced into the hydraulic cylinder 6 so that the gap S between the back surface of the piston 5 and the shaft 9' can be eliminated. The size such as the diameter and the length of the shaft 9 ′ is determined so that the bending rigidity is larger than the deformation rigidity of the housing 1.

Reference numeral 12 denotes an electric motor or a hydraulic motor. The shaft 11 of the motor 12 is supported by a rotation support G. The tip of the shaft 11 of the motor 12 is connected to the rear end of the screw 9 via the joint 10 so that the screw 9 can be rotated. The electric motor or the hydraulic motor 12 may be much smaller than a conventional electric motor or a hydraulic motor for moving a roll chock.

FIG. 3 shows an enlarged view of the joint 10 'of the screw 9 and the shaft 9'. In FIG. 3A, the screw 9 and the shaft 9 ′ are separated,
After the position of the piston 5 is determined, the screw 9 is moved by the motor 12 to eliminate the gap g between the screw 9 and the shaft 9 ', and the shaft 9' is pushed in to fix the retracted position of the piston 5. Conversely, when retracting the piston 5, the screw 9 is drawn out by the motor 12, and then the shaft 9 'and the piston 5 are displaced by the hydraulic pressure of the hydraulic cylinder 6. On the other hand, as shown in FIG. 3B, a spherical portion 14 is provided at the joint portion and is received by the spherical seat 13, so that the screw 9 can be rotated by rotating the screw 9 without rotating the shaft 9 '. 'It is a mechanism that can move. In any case, the structure is such that the rotation of the screw 9 is not transmitted to the shaft 9 ′, and the seal portion 6 ″ of the hydraulic cylinder 6 is formed.
The burden on is small.

While the structure on the left side of the roll chock 3 has been described above, the hydraulic cylinder 6, the screw 9, the electric motor or the hydraulic motor 12 and the like are disposed on the right side of the roll chock 3 as described above. Since the structure is the same as that described above, illustration is omitted.

FIGS. 4 to 6 are front views of the main part of the work roll of the rolling mill, showing the state before and after the roll chock 3 is pressed with an offset force to eliminate the gap. FIG. 4 shows a non-rolled state, in which a gap δ ′ is secured between the roll chocks 3 and the liner 4 in the same state as in the prior art so that the roll can be easily replaced. The gap between the piston 5 and the shaft 9 ′ in the hydraulic cylinder 6 is controlled by the motor 12 according to the movement of the piston 5.

FIG. 5 is a view showing a rolled state or a preparation state thereof. The liner 4 is pressed against the roll chock 3 with an offset force F, the gap δ ′ is 0, and the housing 1 is moved by the offset force F. This shows a state of being deformed by δ. In this case, the piston 5 is fixed so that the retracted position of the piston 5 with respect to the screw 9 is fixed.
The motor 12 is set so that the gap between the shaft 9 'and the shaft 9' becomes zero. FIG. 6 shows a case where the liner 4 has a flat surface. As described above, the rolling mill according to the first embodiment is configured such that the liner 4 can be pressed against the roll chock 3 by the hydraulic cylinder 6.

In the rolling mill configured as described above,
First, roll chock 25, backup roll 22,
The roll gap between the upper and lower work rolls 2 is set to a predetermined value via the roll chock 3 and the work rolls 2, and the transported strip 21 is moved to the upper and lower work rolls 2.
The strip 21 is rolled into a thin steel sheet having a predetermined thickness by receiving the reduction load from the reduction means 24 while rotating the upper and lower work rolls 2 and the backup roll 22 while rotating the work roll 2 and the backup roll 22.

At the time of this rolling, the gap δ ′ of the roll chock 3 can be reduced to zero by pressing the roll chock 3 with the hydraulic cylinder 6 provided in the housing 1. Further, the housing is deformed by deforming the housing by δ in the horizontal direction by the offset force F, and the screw 9 is rotated and displaced by the motor 12, and the retracted position of the piston 5 of the hydraulic cylinder 6 is fixed by the shaft 9 ′. By that, roll chock 3
The effect of the horizontal rigidity on both sides of the housing is exerted on the housing, and the horizontal dynamic rigidity of the roll chock 3 and the work roll 2 is increased, so that horizontal vibration of the rolling mill is less likely to occur.

FIG. 7 shows the relationship between the horizontal displacement of the roll chock 3 and the horizontal reaction force on the roll chock 3 from the housing 1 side. The slope of the graph indicates the horizontal rigidity. (A) is a case where the roll chock 3 is pressed with the offset force F and the deformation amount δ of the housing 1 is positive. When the displacement of the roll chock 3 exceeds δ, the rigidity from the housing post opposite to the displacement direction x does not act, and the inclination (rigidity) decreases. The effective horizontal stiffness is determined by the vibration amplitude ratio η = x ₀ / δ, where x ₀ is the horizontal amplitude of the roll vibration. The larger the η (the larger x ₀ or the smaller δ), the more effective Horizontal stiffness is reduced.

FIG. 2B shows the amount of deformation δ of the housing 1 when the roll chock 3 is not pressed by the offset force F and there is a gap δ ′ between the roll chock 3 and the liner 4.
Is shown. Also in this case, the effective horizontal rigidity is determined by the vibration amplitude ratio η = x ₀ / δ ′, but in this case, η
(When x ₀ is large or δ 'is small), the effective horizontal rigidity increases.

FIG. 8 shows the relationship between the gap amount δ ′ between the roll chock 3 and the liner 4 or the deformation amount δ of the housing 1 and the horizontal rigidity, centered on the vibration amplitude x _{0 to} 0.1 mm. High pressure force, but the vibration in the rolling roll and is rolling under high pressure ratio occurs, if the amount of the gap is greater than the vibration amplitude x ₀ (case of the left than the point A in FIG. 7), the roll chock 3 is passing plate Since it comes into contact only with the housing 1 on either the entry side or the exit side, the dynamic stiffness in the horizontal direction is small, and the horizontal level is maintained regardless of the structure of the hydraulic cylinder 6.

If the gap amount δ ′ is smaller than the point A in FIG.
Since it comes into contact with the housing on the outlet side, it is restrained and the rigidity in the horizontal direction increases. Furthermore, as the housing deformation amount δ becomes larger due to the offset force F, the roll chock 3 almost always comes into contact with the housing 1 on both the entrance side and the exit side, and the horizontal rigidity increases. In this case, when only the normal hydraulic cylinder 6 is installed,
When only the lower part of the above-mentioned fixing mechanism is installed in the hydraulic cylinder 6, the horizontal rigidity greatly differs between the case where the above-mentioned fixing mechanism is installed vertically.

When a mechanism for fixing the piston 5 in the hydraulic cylinder 6 of the present invention is installed in the upper and lower roll system, the force on the roll is directly transmitted through the shaft 9 ′ and the screw 9 without passing through the oil 15. Stiffness is maximized. Thus, by pressing the roll chock 3 against the housing 1 by the hydraulic cylinder 6 and mechanically fixing the piston 5, the gap δ 'and the amount of horizontal deformation δ of the housing due to the offset force F can be managed, and the oil has low rigidity. Therefore, the horizontal dynamic stiffness at the time of rolling is significantly increased as compared with the conventional rolling mill, and the occurrence of vibration at the time of rolling can be reduced.

However, when the gap δ ′ is 0 or the housing deformation δ is positive, a frictional force is generated in the vertical direction to press down the roll chock 3, which may make it difficult to control the thickness with high accuracy. , Rolling elements 16 and 16 ′ against the pressing surface of liner 4 for holding chocks 3
Alternatively, by installing the grease pad 17, the friction coefficient is reduced, the vertical movement of the roll due to the preload is made smooth, and the accuracy of the thickness control can be secured without obstructing the thickness control.

(Second Embodiment) Next, a second embodiment shown in FIGS. 9 and 10 will be described. The rolling mill according to the first embodiment described above includes a shaft 9 ′, a screw 9, an electric motor or a hydraulic motor 12 for each of the hydraulic cylinders 6 on both sides of the roll chock 3,
Although a means for fixing the retreat position of the piston 5 is provided, in the rolling mill according to the second embodiment, means for fixing the retreat position of the piston 5 only to one of the hydraulic cylinders 6 is provided. It is. That is, in the configuration shown in FIG. 9, the shaft 9 ′, the screw 9, and the motor 12 are provided only on the right side of the roll chock 3. The liner 4 is provided with rolling elements 16, 16 'and a grease pad 17 similar to those shown in FIG. On the other hand, FIG. 10 shows a case where the liner 4 has a flat surface.
Other configurations are the same as those of the first embodiment, and description thereof will be omitted.

(Third Embodiment) Next, a rolling mill according to a third embodiment with respect to FIG. 11 will be described. In the rolling mill according to the third embodiment, the electric motor or the hydraulic motor 12 for rotating the screw 9 to move the shaft 9 'is used.
A hydraulic cylinder 6 'is provided to assist the electric motor or the hydraulic motor 12 when the power is insufficient.
As shown in FIG. 11, the piston of the hydraulic cylinder 6 '
It is connected to the screw 9 via a joint 10 '' and a shaft 11 ', while the electric or hydraulic motor 12
Has a threaded portion 19. Motor 12
Rotates the screw 9 by rotating the shaft 11 'by means of the screw portion 19 so that the screw 9 can be taken in and out. Other configurations are the same as those in the first and second embodiments, and a description thereof will be omitted. According to the third embodiment,
The screw 9 can be smoothly taken in and out.

(Fourth Embodiment) Next, a fourth embodiment shown in FIG.
A rolling mill according to an embodiment will be described. In the fourth embodiment, a plurality of hydraulic cylinders 6 for bringing the liner into contact with the roll chock 3 are provided. In the case of FIG. 12A, two liners 4 are provided which are in contact with the roll chock 3, and each of them is provided with a hydraulic cylinder 6, a shaft 9 ', a screw 9, and the like. On the other hand, in the case of FIG. 12B, one liner 20 is provided, and the pistons 5 of the two hydraulic cylinders 6 are connected to this. Each screw 9 is an electric motor or a hydraulic motor 1
2 rotates the screw portion 19 and the joint 1
0 and are configured to be rotated.

Although the two screws 9 are driven by one electric motor or one hydraulic motor 12 in the drawing, if the position of the roll chock 3 is shifted vertically, The upper and lower screws 9 may be controlled by independent electric motors or hydraulic motors. As described above, the configuration in which the roll chocks are pressed by the two hydraulic cylinders 6 is suitable for use in controlling the position of a large roll, and can be used, for example, to control the position of a backup roll. Other configurations are the same as those shown in the previous embodiment, and the description thereof will be omitted.

Although the present invention has been specifically described based on the illustrated embodiment, the present invention can be similarly applied to a cross rolling mill and a non-cross type rolling mill. Furthermore,
In the case of a cross rolling mill, the present invention can be applied to any of a case where only a work roll is a cross type and a backup roll is not a cross type and a case where both a work roll and a backup roll are a cross type.

The present invention is not limited to the above-described embodiment, and it goes without saying that various changes may be made to the specific structure and structure within the scope of the present invention as set forth in the appended claims. For example, in the above embodiment, the work roll 2 and the roll chock 3 have been described. However, the present invention can be similarly applied to the backup roll 22 and the roll chock 25 thereof. Can be further increased.

In the above-described embodiment, the liner 4 is provided at the tip of the piston 5 of the hydraulic cylinder 6 to press the roll chock. However, in the case of a cross rolling mill, the cross head is used without using the liner 4. A configuration in which the piston is pressed by the piston 5 of the hydraulic cylinder 6 may be employed. Furthermore, in the illustrated embodiment, the shaft 9 ′ that is abutted on the piston 5 of the hydraulic cylinder 6 at the rear is described as having a configuration that does not rotate. However, the shaft 9 ′ may be configured to rotate, and the shaft 9 ′ may be configured to rotate. Is determined according to the performance of the seal 6 ″ at the portion penetrating the hydraulic cylinder 6.

[0038]

As described above, according to the present invention, a pair of upper and lower work rolls, a roll chock supporting the work roll, and a housing for pressing the roll chock horizontally are provided in the housing of the rolling mill. A rolling mill provided with a hydraulic cylinder on both sides or one side of the roll cylinder, and a liner or a work roll crosshead for always pressing the roll chock in a horizontal direction at a tip of a piston of the hydraulic cylinder in a direction perpendicular to the roll chock. A rolling mill having a configuration having:

In the rolling mill of the present invention having the above-described structure, the liner or the work roll crosshead is pressed against the work roll roll chock by the hydraulic cylinders provided on both sides or one side of the housing, and the liner and the work roll crosshead or the work roll crosshead and the roll chock are pressed. The gap between them is zero, and the offset force (preload) more than zero is applied by the hydraulic cylinder to slightly deform the housing, thereby increasing the horizontal dynamic rigidity of the rolling mill with respect to the work roll. Thus, vibration of the rolling mill during rolling can be reduced, and high-efficiency rolling can be performed.

In the rolling mill according to the present invention, in which the rolling element or the grease pad is mounted on the contact surface of the liner or the crosshead which comes into contact with the roll chock, the liner pressed against the roll chock and the vertical direction of the crosshead Therefore, the vibration of the rolling mill during rolling can be reduced without hindering the thickness control.

Further, in the rolling mill according to the present invention, a shaft for mechanically fixing the retracted position of the piston of the hydraulic cylinder, a screw mounted on the housing for displacing the shaft, and a motor for rotating the screw are provided. In the configuration that has the configuration, the piston of the hydraulic cylinder that presses the liner or the crosshead against the roll chock does not pass through the oil having low rigidity in the hydraulic cylinder, and the shaft that is in contact with the back surface of the piston as described above. And the housing is fixed to the housing via a screw behind the shaft, so that the horizontal rigidity of the rolling mill can be reliably increased, and horizontal vibration of the rolling mill is hardly generated.

As described above, according to the present invention, there is provided a rolling mill in which the horizontal rigidity of the rolling mill with respect to the work roll is increased to reduce the vibration of the rolling mill which occurs during rolling, thereby improving the rolling efficiency. Is done.

[Brief description of the drawings]

FIG. 1 is an explanatory view showing a main structure of a rolling mill according to a first embodiment of the present invention.

FIG. 2 is a drawing showing the structure of the liner in FIG. 1,
(A) and (b) show a case where a spherical rolling element is mounted, (a) is a side view, (b) is an end view, and (c) is a case where a cylindrical rolling element is mounted. (D) and (e) show the case where a grease pad is used,
(D) is a side view, (e) is an end view, (f) is a side view showing a case where a laminated rubber liner is installed.

3A and 3B are explanatory views showing a connection state between a screw 9 and a shaft 9 'in FIG. 1, wherein FIG. 3A shows a case where both are separated from each other, and FIG. 3B shows a case where they are rotatably connected. .

FIG. 4 is an explanatory diagram showing a state in which the rolling mill according to the first embodiment of the present invention is in a non-rolling state.

FIG. 5 is an explanatory view showing a case where the rolling mill according to the first embodiment of the present invention is in a rolling state or a preparation state thereof.

FIG. 6 is an explanatory view similar to FIG. 5, showing a case where the liner has a flat surface;

FIG. 7 is a diagram showing the relationship between the displacement of the roll chock and the reaction force from the housing to the roll chock, and FIG.
(B) shows a case where the housing is deformed by applying an offset force to the housing, and (b) shows a case where no offset force is applied to the housing due to a gap between the roll chocks and the liner.

FIG. 8 is a diagram showing changes in the amount of deformation of the housing and the dynamic stiffness in the horizontal direction of the rolling mill due to the offset force on the housing.

FIG. 9 is an explanatory view showing a rolling mill according to a second embodiment of the present invention, in which a rolling element or a grease pad is used for a liner.

FIG. 10 shows a rolling mill according to a second embodiment of the present invention,
Explanatory drawing when a liner is flat.

FIG. 11 is an explanatory view showing a rolling mill according to a third embodiment of the present invention.

FIG. 12 is an explanatory view showing a rolling mill according to a fourth embodiment of the present invention, wherein (a) shows a case where two liners are used, and (b) shows a case where one liner is used.

FIG. 13 is a side view showing a conventional four-high rolling mill, in which (a) shows a general four-high rolling mill and (b) shows a general four-high rolling mill.

FIG. 14 is an explanatory view showing an inner narrowing deformation of a housing due to a rolling load in a rolling mill.

FIG. 15 is an explanatory diagram showing, in an enlarged manner, the structures of a work roll, a roll chocks, and a cross head in the four-stage cross rolling mill shown in FIG. 13B.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Housing 2 Work roll 3 Roll chock 4 Liner 5 Piston 6 Hydraulic cylinder 6 'Hydraulic cylinder 6' 'Seal 7 Hydraulic piping 8 Hydraulic piping 9 Screw 9' Shaft 10 Joint 10 'Joint 10' 'Joint 11 Shaft 11' Shaft 12 Electric motor Or hydraulic motor 13 spherical seat 14 spherical portion 15 oil 16 spherical rolling element 16 'cylindrical rolling element 17 grease pad 17' laminated rubber 17 '' oil-resistant rubber 17 '' 'metal plate 18 shaft 19 screw portion 20 liner DESCRIPTION OF SYMBOLS 21 Strip plate material 22 Backup roll 23a Housing liner 23b Cross head 24 Roll-down means 25 Roll chock 26 Cross screw or hydraulic cylinder 27 Pull back cylinder

Claims (4)

[Claims] 1. A roll mill comprising a pair of upper and lower work rolls, a roll chock for supporting the work rolls, and hydraulic cylinders on both sides or one side of the housing for horizontally pressing the roll chock. A rolling machine characterized by having a liner or a work roll crosshead for always pressing the roll chock in a horizontal direction at right angles to the roll chock at the tip of a piston of the hydraulic cylinder. 2. The rolling mill according to claim 1, wherein the work roll or the work roll and a backup roll supporting the work roll are configured so that a cross angle can be set. 3. A rolling element or a grease pad is mounted on a contact surface of the liner or the work roll crosshead which is in contact with the roll chock.
Or the rolling mill according to 2. 4. A hydraulic pump comprising: a shaft for mechanically fixing a retreat position of a piston of the hydraulic cylinder; a screw installed in the housing for displacing the shaft; and a motor for rotating the screw.
The rolling mill according to claim 1.